Multi-zonal monofocal intraocular lens for correcting optical aberrations

Abstract

A multi-zonal monofocal opthalmic lens comprises an inner zone, an intermediate zone, and an outer zone. The inner zone has a first optical power. The intermediate zone surrounds the inner zone and has a second optical power that is different from the first power by a magnitude that is less than at least about 0.75 Diopter. The outer zone surrounds the intermediate zone and has a third optical power different from the second optical power. In certain embodiments, the third optical power is equal to the first optical power.

What is claimed is: 
     
       1. A multi-zonal monofocal ophthalmic lens comprising:
 an optic disposed about an optical axis comprising a first lens surface and a second lens surface disposed opposite the first lens surface; 
 the first lens surface comprising a plurality of zones, including:
 a first zone having a finite radial width and a sag surface characterized by a first base radius of curvature value and a first asphericity constant; and 
 a second zone surrounding the first zone and having a finite radial width and a sag surface characterized by a second base radius of curvature value and a second asphericity constant; 
 
 the radius of curvature values are unequal, the asphericity constants are unequal, or the radius of curvature values are unequal and the asphericity constants are unequal; 
 the zones configured to focus light entering the entire optic from a distant point source to substantially a single point, the lens having a maximum Diopter power difference between any two zones of the lens that is less than 0.75 Diopters. 
 
     
     
       2. The multi-zonal monofocal ophthalmic lens of  claim 1 , further comprising a third zone surrounding the second zone and having sag surface characterized by a third base radius of curvature and a third asphericity constant. 
     
     
       3. The multi-zonal monofocal ophthalmic lens of  claim 2 , wherein:
 the first zone has a first optical power, the second zone has a second optical power, and the third zone has a third optical power; 
 the second optical power differs from both the first and third optical powers by a magnitude that is less than or equal to about 0.65 Diopter. 
 
     
     
       4. The multi-zonal monofocal ophthalmic lens of  claim 1 , further comprising a diffractive grating disposed on the first surface. 
     
     
       5. The multi-zonal monofocal ophthalmic lens of  claim 1 , further comprising a diffractive grating disposed on the second surface. 
     
     
       6. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the first base radius of curvature is equal to the second base radius of curvature. 
     
     
       7. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the zones are adapted to focus incoming light rays to form an image from an object and the second zone is adapted to compensate for optical aberrations in the image resulting from implanted intraocular lens decentration of greater than at least about 0.1 mm. 
     
     
       8. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the zones are adapted to focus incoming light rays to form an image from an object and the second zone is adapted to compensates for optical aberrations in the image resulting from implanted intraocular lens tilt of greater than at least about 1 degree. 
     
     
       9. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the first lens surface is further characterized by at least one boundary parameter that is selected to smoothly connect the first zone with the second zone. 
     
     
       10. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the zones are configured to reduce spherical aberrations. 
     
     
       11. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the ophthalmic lens has a nominal optical power that is positive and the second zone has a negative spherical aberration that is selected to reduce spherical aberrations. 
     
     
       12. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the second base radius of curvature is greater than first base radius of curvature. 
     
     
       13. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein an average MTF efficiency of the lens is higher than an average MTF efficiency of a spherical lens. 
     
     
       14. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein an MTF efficiency at a spatial frequency of 50 cycles/mm of the lens is higher than an MTF efficiency at a spatial frequency of 50 cycles/mm of a spherical lens. 
     
     
       15. A multi-zonal monofocal ophthalmic lens comprising:
 an optic disposed about an optical axis comprising a first lens surface and a second lens surface disposed opposite the first lens surface; 
 the first lens surface comprising a plurality of zones, including:
 a first zone having a finite radial width and a sag surface characterized by a first base radius of curvature value and a first asphericity constant; and 
 a second zone surrounding the first zone and having a finite radial width and a sag surface characterized by a second base radius of curvature value and a second asphericity constant; 
 
 the radius of curvature values are unequal, the asphericity constants are unequal, or the radius of curvature values are unequal and the asphericity constants are unequal; 
 the lens having a maximum Diopter power difference between any two zones of the lens being less than 0.75 Diopters. 
 
     
     
       16. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the first zone and the second zone are disposed adjacent to one another. 
     
     
       17. The multi-zonal monofocal ophthalmic lens of  claim 1 , further comprising a smooth transition between the first zone and the second zone. 
     
     
       18. The multi-zonal monofocal ophthalmic lens of  claim 1 , wherein the zones are configured such that light entering the entire optic from a distant point source falls within the range of the depth-of-focus of a spherical lens having a focal length equivalent to a focal length of the multi-zonal monofocal ophthalmic lens.